In a nutshell: AT&T is expanding the iPad 3G's fair, easy-to-understand data pricing to their entire network, tethering will cost $45/mo (including the required 2 GB data plan), and iPhones will finally finally finally be able to tether in the U.S.
There's a lot of complaining about these changes today, mostly centered around AT&T dropping their $30 "unlimited" plan (actually a 5 GB plan, with exorbitant overage charges), as well as the usual litany on how awful AT&T's service is. This reminds me of an old joke about two ladies in a restaurant. One lady says "I hate this place! The food is terrible!" And the other lady says, "Yes, I agree! And the portions are so small!"